Showtime
by chrissie0707
Summary: Missing scenes/tag for 10X09 "The Things We Left Behind." Warnings for language and violence. PART IV OF IV POSTED: There's more than enough blood already on Sam's hands as he grabs Dean's grimy face and grips tightly, forcing his brother to meet his wide-eyed gaze. Without preamble or ceremony or opportunity to entertain denial, he demands, "tell me you had to do this."
1. Part I

_Author Note: My muse and brain were giving me crap, so the Promptmaster gave me a prompt, and then halped me get this posted when issues arose. Thanks, dork face._

 _Takes place near the beginning of 10.09 "The Things We Left Behind," between Dean waking up from his nightmare and Sam bringing him a sandwich._

 _EDITED 5/23/16: The muse and muse's assistant are at it again, and while this was going to be a one shot, and then a two-parter, it's now looking to be a four part story weaving in missing scenes for the entire episode, and a tag. So stay tuned. There will be more coming soon._

* * *

 **Showtime**

 _Part I_

* * *

 _The blood is everywhere._

 _Hanging in the air; a thick, familiar tang that coats the back of his throat as he pulls in ragged, noisy breaths._

 _In his hair and dripping from his face and coating his hands._

 _Definitely on his hands. Hands that are trembling, his right still gripping a similarly blood-caked knife where he kneels in the center of the room._

 _In the center of the carnage. There are nameless bodies strewn around him, cut and slashed to match the cast-off painting the walls and hardwood beneath his knees. They'd been butchered, clearly by his hand._

 _There's no context to be found, no_ before _. No reason_ _given for what he's done._

 _He feels…frightened, at first. Shocked. Sorry._

 _But those are fleeting emotions because, more than anything, he feels_ good _._

Dean jackknifes like he's coming up for his first breath in five minutes, sucks in a desperate pull of oxygen that has his head swimming and his limbs tingling. Except the spot where the Mark of Cain is as good as scalding against the tender skin of his right forearm, pulsing painfully to match his racing heart.

He moves immediately to rub at the spot, to acknowledge the burn, but it doesn't make the feeling abate. He looks around with a wide-eyed glance, expecting to find blood on the walls and bodies on the floor, but he's in his room, in the bunker. Alone.

 _Jesus._ Dean releases his arm and scrubs a hand down his face, works to catch his breath. There's a tickle in his hair, but when he drags his panicked fingers up over his head his palm comes away slicked with cool sweat, not warm, tacky blood.

He's had his fair share of nightmares over the years, but this one felt different.

It _feels_ different.

On his arm, the Mark is burning still. It's taking control. Showing him something, telling him what it wants. Making demands he won't be able to avoid giving into forever.

He'd told Sammy he felt like himself, killing those vamps, doing the job the way it needed to be done. Said it was the first time he hadn't felt like the damn thing was pushing him into violence.

He'd told Sammy _bullshit._ Fed his little brother a story to keep him from worrying, because Dean's already given the kid enough to worry about for a damn lifetime.

The Mark is _always_ pushing him. Always burning hot, even when he sleeps.

The fire is spreading, the burn growing in his chest and his gut, and suddenly Dean is rolling off of the bed as though John Winchester himself is shouting from the doorway for his boy to get his lazy ass moving, makes it to the sink in time to heave a sparse mess that's a little bloody but mostly just last night's whiskey.

He moves quickly to run the tap, cups his hands beneath the cold water and sucks in a mouthful. Rinses and spits, then tosses another handful over his face. He leaves the faucet running, braces his palms on either side of the shallow basin and stares into the bottom, waits for the last beads of water to drip from his chin before finally raising his gaze to take stock of his reflection.

He looks like hell. Like the ass-end of two-day-old roadkill, and there's no way he can face Sammy this way. Not with these red eyes ringed with dark circles in a pasty white face. Not with liquor and vomit on his breath.

Not when he's been telling his brother that he's gotten back to feeling like himself.

Dean shuts off of the water and glances down at his watch, is both appalled and impressed by the hour. It's pretty early, even for Sam, and he should be able to navigate the bunker's corridors with minimal chance of bumping into the little insomniac. And coffee, if he can manage to keep it down, is sure to do a world of good in the way of making himself presentable.

He hadn't even made it out of his jeans before falling into bed, so he's halfway dressed already, and doesn't look to do more than grab up the first button-down he lays eyes on. He's dragging a probably-clean blue shirt over his sweat-chilled tee when a shooting pain in his right arm doubles him over and tears a strangled yelp from his lips.

Once the pain fades to a more bearable twinge, Dean straightens and goes about rolling the cuffs of his sleeves, fingertips lingering over the raised, hot-to-the-touch mark below his elbow before he shakes it off as well as he can, and makes his way out into the still, silent hallway.

* * *

Of all the antiquated items they've had to update since moving their shit into the bunker, Dean doesn't know how they haven't yet gotten around to dealing with the damn coffeemaker.

It's loud, and it takes too long to brew, and he's not even sure he wants the coffee anymore. He can't seem to forget the images, the _feelings_ from his nightmare, and when coupled with the persistent ache in his arm it's making him nauseous, and he doesn't really need a cup of hot liquid to add to the molten heat already spreading throughout his body.

Dean rolls his neck and leans against the counter, focuses his weight down through his arms and stares at his hands where they're flattened atop the stainless steel. His right hand jumps and he quickly makes a fist, presses his knuckles against the countertop and closes his eyes against the fiery lance shooting up and down his arm. When he opens them again, the coffee is ready, and he scratches his chin before moving to drag a plain white mug upright from the drying mat.

The mugs in the bunker's store are pitifully small, but that's okay, because Dean's drinking less and less coffee these days. Has other thirsts now, and more often than not he's just going through the motions when he pours a cup, or accepts one from Sam.

He's contemplating altogether giving up on the coffee, with trading it for something that will do better to calm him, when he notices the tremor in his right hand. About the same time that he realizes there's blood welling in his mouth from how hard he's got his bottom lip caught between his teeth. He winces an acknowledgement of the steadily growing pain in his arm and then tries to relax the muscles in the traitorous limb, drawing slow breaths in and out.

To no avail, as the tremor becomes a full-blown shake and the pain continues to grow still, rooted in the Mark but no longer confined to his forearm. It branches up to wrap around Dean's shoulder joint and bleeds into his chest, snakes like thorny tendrils through his veins to his circle his wrist and wriggle down into each finger where they're keeping a tentative, white-knuckled grip on the porcelain mug.

He tries to still the shake in his hand, to compartmentalize the pain in his…everything else, but it's become too deeply embedded in his very core, and in a sudden, searing flare that steals his vision and leaves him gasping, Dean loses his hold on any semblance of control over his own body, and of the mug. It slips from his fingers and drops to the tile, explodes onto the kitchen floor in tiny, jagged shards.

The _crash_ sends Dean staggering back into the edge of the counter, and when he looks down he doesn't see pieces of a busted mug in the mess at his feet; he sees remnants of his nightmare. Splatters of dark blood spilled across the tiled floor, evidence of death wrought by his hands.

The pain recedes just as quickly as it had reared, not gone but not unmanageable, and Dean finds himself rubbing at the spot where the Mark is concealed by his shirtsleeve.

They're not other people, and the crash of the shattering mug has surely been enough to wake his brother all the way in his room. Enough to bring Sam running in at any moment, with questions Dean can't, or won't, answer.

And it does. He's barely gotten the mess cleaned and settled himself at the table before Sam appears in the doorway. Must've fallen asleep much the same way Dean had, in the way of fully clothed, though likely due more to late-night research than anything like of the half-shot bottle of Beam nestled next to his own bed.

Dean feigns a yawn and does his best to act enthralled by something on the screen of his cell phone before raising his eyebrows in acknowledgment of his brother. "Bad dream?" he asks, a bit taken aback by the hoarseness of his own voice. He clears his throat, rubs at his eyes. "Need me to check your closet for monsters?"

"Shut up. I thought I heard…" Sam braces a hand on the doorframe and glances around the room, eyes narrowing. "Guess it was nothing." He taps his fingers on the frame before stepping fully into the kitchen. "You make any coffee yet?"

"Hmm? Oh, yeah." Dean throws a hand in the direction of the percolator. There's no denying the lingering shake there, and he folds a fist against the tabletop, moves quickly to throw a distraction at his brother. "Diggin' the bedhead, Sammy."

Sam rolls his eyes and runs his fingers through his tousled hair as he moves to the counter. He stops and shoots Dean a quizzical look. "Pot's still full."

"Yeah," he answers quickly. "That's the second one."

Sam raises his eyebrows, nods as he turns to grab up a mug. "So then you're gonna be fun today, huh?"

"I'm always fun."

"Right." Sammy was raised in a black coffee kinda household, but it's not his preference, and his eyes roam the kitchen for sugar or milk, whichever is closer. "You eat anything?"

Dean's stomach roils, and whatever might be left over from earlier makes a run at exiting his mouth. He squashes the urge and swallows. "Nope," he answers tightly, pushing up from the table.

Sam sips his coffee and watches him make his way out. "Want me to make something?"

Sam and kitchens don't tend to make the sort of dynamic duo Dean likes to tangle with, but he waves vaguely with his left hand as he brushes past his brother, keeping his right curled into a tight fist at his side. "Yeah, sure. Knock yourself out."

He knows he has appearances to keep up and can't go as far as retreating back to his room, sinks into a chair at one of the long tables in the bunker's main chamber. Spots his laptop lying on the polished surface and drags it close, searching desperately for a distraction, for anything to take the Mark and its demands off his mind. Figures an old _Stooges_ episode is good enough, and Dean goes to work practicing the smile Frank Devereux had once warned him was one of the most vital parts of living this life, and even throws a few laughs in for good measure.

After a few minutes, he no longer notices the tremble in his right hand, and after a few more, Dean might even forget that he's pretending.

"What are you laughing at?"

Until Sam enters the room, anyway. Dean's eyes dart over at his brother's approach. It ain't exactly breakfast on the plate, but Sammy knows his strengths, and even an idiot would have a hard time mucking up a grilled cheese sandwich. He swallows, forces the grin to stretch wider across his face.

 _Showtime._

* * *

 _To be continued_...


	2. Part II

_Author Note: Hey there. So my muse has turned this one-shot not only into a two-shot, but into a four-parter of missing scenes for the episode. Scenes I'd completely forgotten that I was wanting until I rewatched the ep in preparation of completing this homework assignment. Part III will be the unseen fight in Randy's house, and Part IV will tag the ep._

 _I thank you for the reviews, and the follows, and promise that the next two parts will be along shortly._

* * *

 **Showtime**

 _Part II_

* * *

It's not for lack of trying that Sam hasn't been getting much sleep lately. Too much that has transpired lately remains fresh in his mind, like a wound scabbed over but not fully healed, still plaguing him with a constant itch of paranoid nervous energy that he can't seem to scratch and does well to drive away any hope of real, effective rest.

The demon in his brother – the demon that _was_ his brother – might be gone, but an obvious thirst for bloodshed and violence lingers inside Dean, a feral, unfamiliar energy that Sam had glimpsed even before the demon. Something about his brother that frightens him more and more as the days wear on. As the Mark of Cain wears on.

Dean had claimed he was feeling like himself when he dispatched of the vamps in Minnesota, but in juxtaposition to such a statement was the case of the shapeshifter he'd killed just the previous week, the one he'd emptied a clip into without any explanation to sufficiently put Sam's worried, restless mind at ease.

" _I got a little anxious. Wanted to make sure it was done right – plain and simple."_

It – the job – was done and done right when the shifter was dead from strike of the first bullet. End of story. That's the way they were raised, and _trained_ , and if anyoneshould be expected to respect the way John Winchester trained them, it's _Dean_. Additional shots are pointless. A waste of time, energy and ammunition. Dad would have ripped him a new one for what he did in that house; Sam could only gape dumbly.

There are times like this when he barely recognizes his brother, and other times the man seems so filled to the brim with DEAN he might overflow. Almost like he's trying too hard, or like the Mark is attempting to push Dean out of himself and turn him into a brand new animal. A theory that might not be so off the, well, mark.

Sam knows his brother is only pretending when he says he's okay, but while he'd typically be the first in line to call Dean on his bullshit, he's having a hard time finding the benefit in saying, _Dean, you're not acting_ quite _as rabid and bloodthirsty as I'm worried you feel._

And besides, sometimes that's _exactly_ how he's acting.

A little anxious, Dean had said. His first kill since he…came back. That's all. Nothing to do with the demon, and certainly not with the Mark of Cain. But if this is just Dean when he's anxious – a feather-light finger on the trigger and that dark, cold look in his eyes as he pushes past the kill into _overkill_ – then maybe it's best they don't take on another job for a while, until Sam's found a way to rid his brother of the damn thing.

It's a plan without anything approaching a concrete timeline, and one he hasn't actually floated past Dean yet. Sam's once more sitting up in the early hours of the morning with a long-empty coffee mug and a stack of large, dusty tomes from the deepest shelves of the bunker, fighting the rising burn in his eyes from another sleepless night as he struggles to find _anything_ of use.

Frustrated, Sam shoves away the thick, leather-bound book to scrape across his desktop and leans back in his chair, scrubbing roughly at his eyes. Another bust. Another dead end. There's a strange nagging feeling in his belly, some sort of gut instinct telling him they're on the clock here, but he's not sure what exactly they're counting down to. Nothing good.

He peeks at his watch, figures Dean can't possibly be expected to be up for another few hours, and it couldn't hurt to give sleep another go before the bunker's halls are filled with rock music and stomping boot heels. Sam's yawning and pushing away from his desk when his ears perk to the sound of a far-off _crash._

Perhaps to compensate for Dean's increasing inconsistency in planning and forethought, there's a long moment of hesitancy before Sam rushes out of his room to investigate the sound. A moment where he debates the legitimacy of possible danger in the bunker, and the need for a weapon. He decides against arming himself, and lets his ears and instincts lead him through the halls straight to the kitchen.

He's surprised enough to see his brother there, but more so to see him settled at the empty table, the TV dark in the corner and without so much as a cup or plate to explain his presence here. And then, even more so by how damn _bad_ the man looks.

Because Dean looks – to put it mildly – like _shit_. Backend of a week-long bender shit. Broadsided by a tractor trailer shit. He seems generally rumpled, and his complexion has taken on an unhealthy, sallow pallor. There's a worrisome hint of dried blood in the creases of his bottom lip that sets Sam's heart tripping.

Dean barely glances up to register his approach, gripping the cell phone in his hand like a lifeline. Or, more likely, an excuse. "Bad dream?" He sounds like nearly as much shit as he looks, rough and hoarse. Seems to notice it for himself, too, as he clears his throat and rubs his eyes. "Need me to check your closet for monsters?"

"Shut up," Sam says with a frown, the response seemingly dragged automatically from him, though he wants nothing less than to give in to these antics. "I thought I heard…" He _knows_ what he heard, and braces a hand on the doorframe as he ducks farther into the kitchen, surveying the room for broken objects. "Guess it was nothing." _Or at least, nothing we're gonna talk about right now._ If he hadn't had that moment's pause in his room, he might have been able to catch his brother in the act of…whatever had drawn his attention, and put an end to this entire ordeal.

Sam taps his fingers on the frame before stepping completely into the room, narrowing his gaze appraisingly at Dean, who won't meet his eyes and seems wired and twitchy in a possibly dangerous way. "You make any coffee yet?"

"Hmm? Yeah." Dean throws a hand in the direction of the coffeemaker. There's a faint shake there, but it's not so faint that Sam can't see it from across the room. Dean swallows, drops his hand to his lap and his gaze back to his phone. "Diggin' the bedhead, Sammy."

Sam rolls his eyes, smooths his hair on the way to the counter. "Pot's still full," he observes, shooting a glance back at his brother.

"Yeah," Dean answers, quickly enough to give himself whiplash. "That's the second one."

Sam raises his eyebrows at the implication of his brother downing an entire pot of caffeine, though it might explain the shake and general off-ness of the man this morning. He nods as he grabs a mug, taking note of the ringed impression in the foam drying mat signifying a cup missing already. "So then you're gonna be fun today, huh?"

"I'm always fun." But Dean's words are forced and hollow, his mind clearly preoccupied.

"Right." Sam pours himself a cup of coffee, and can't help the habit of scanning the kitchen countertops for milk or sugar, though he knows Dean won't have put any out. "You eat anything?"

He's guessing it was a nightmare that has his brother up and about so much earlier than he's typically known for, because that's always when Dean feels his most vulnerable, and most exposed, and could definitely account for the shiftiness at the table at least as much as the excess of coffee. Sam can relate, of course. Has a long, torrid history with rough nights and elusive slumber, and knows exactly how laid-bare it feels to wake to a face full of all the things you most fear might reside within yourself.

He sees it now in his brother's eyes as Dean looks up at him.

"Nope." The response is tight and Dean moves immediately to push up from the table, maybe even a bit green at the mention of food.

Sam sips his coffee as he studies his brother's jerky, deliberate movements, then dips his eyes to the liquid in the cup. The drink's not exactly hot and tastes old, and has separated, looking oily on top. He swallows it anyway, doesn't call attention to Dean's blatant lie. Throws another lure into the water, though, just to see how far he's willing to go with this charade. "Want me to make something?"

Dean brushes past him without making any further eye contact, right hand curled into a tight fist and pressed against his side, almost like it's hurting him. "Yeah, sure. Knock yourself out."

Then he's gone, and Sam drops his own charade, lets the mug of disgusting, lukewarm coffee settle on the counter with a _thunk._ He honestly doesn't know what's worse; that Dean feels the need to put on such a show, or that he's letting the jackass think he's buying it.

This is exactly why Dean thinks he's good at this, at hiding things from his brother. He's not. Not at all. Sam just continues to play along and let him think he is because, sometimes, the alternative just seems so much worse.

Sam has all the pieces now, and he can put two and two together well enough. Can add up _loud crash_ , _missing mug_ , and _shaky hands_ and figure out easily what's gone down. What he doesn't know is exactly why Dean is so set on hiding such a seemingly small accident. Because, in their line of work? They break shit, sort of a lot. On a daily basis. And Dean's always been the kind of guy to embrace his less graceful of moments, almost as much as he does Sam's. To laugh it off and order up another round.

Something about the Mark of Cain – and what it's done to him – has granted Dean a sort of self-consciousness he's never before been burdened with, and seems remarkably out of place in circumstances when it's just the two of them.

Or it's simply a hint of something much, much worse lying in wait below the surface.

In any case, Dean certainly didn't appear to be in any hurry to eat, so Sam heads back down the hall to quickly shower and change into clean clothes as he waits out a fresh pot of coffee to drip infuriatingly slowly from the ancient brewer.

He hears Dean banging around in the main room as he makes his way back to the kitchen, and has to figure the fact his brother hasn't just taken off for higher ground has to count for something. Has to be progress.

It strikes Sam while he gathering supplies that he can't honestly remember the last time he saw Dean finish a meal, and he gets so caught up in his worry and musing that he burns the first sandwich, and _scorches_ the second. The third one turns out well enough, and he smiles a little as he scoots the grilled cheese onto a plate, thinking about how the tales of his continuing failures in the kitchen might actually bring Dean a real laugh, and that's something he'd sure like to hear more often these days.

So it almost seems a blessing when he hears his brother's laughter as he approaches the main room with a hot, cheesy offering of not-exactly-breakfast in hand. Dean's squared up in front of his laptop and leaning casually in his chair as he looses another of those loud, gruff chuckles that seems…forced.

Sam slows a bit at the steps and takes a breath, but finds himself tensing up anyway as he pushes on toward Dean. "What are you laughing at?"

Dean startles a bit as he looks over his shoulder – another new something that has Sam on edge, because he doesn't like how often his brother appears caught off-guard these days. Like he's all reactive, and not quite watching his back like he should. He recovers in a blink, motions to the screen of his computer, where he's watching an episode of _The Three Stooges_. "Hey, hang on, you gotta see this. It's a classic."

It's also classic Dean. Sam's spent years taking note of and studying all of the different ways his brother deflects, or overcompensates, or shuts everyone else out. This isn't anything he's never seen before, though it kills him a little to know just how disingenuous the entire scene is.

"I'm glad you're feeling better," he says, a general statement that still comes out almost a concerned inquiry.

"Oh, yeah. Better than ever."

His color's better at least, and the blood is cleaned from his lip, Sam notices as he settles into the chair next to his brother.

"Oh. Hello, beautiful," Dean greets the sandwich, then tears into it with gusto, eyeing his brother as he takes a big bite and leaves a gooey string of cheese hanging from his chin in a throwback to old-school Dean slobbery.

He's getting sloppy in his desperation to hide whatever is happening to him. Whatever is happening _inside_ of him. Sam frowns, quickly covers it with a smile. "You want some alone time with that thing?"

Dean shakes his head, mumbles something unintelligible that gets lost in the mess of bread and cheese in his mouth.

"You sure?"

He's not asking about the sandwich, and they both know it.

"Yeah, yeah." Another deflection, as Dean won't even look at him any longer. "Watch this." Mouth still full, he taps at the keys with greasy fingers and plays the episode.

He's laughing too much, and too big, but it's an infectious sound Sam doesn't hear anywhere near enough, and he finds himself laughing alongside his brother.

Then his eyes catch sight of the Mark of Cain and it smothers the little brother in him; puts the experienced hunter on high alert. They can play all they want, but he knows better than to ignore these instincts. Things with Dean – and with the Mark – they're going to come to a head. Soon.

But for now, he smiles when Dean smiles, and he laughs when Dean laughs. Sam can't summon the strength to _mean_ any of it, but he has to try, for Dean.

For now, it's showtime.

* * *

 _To be continued..._


	3. Part III

**Showtime**

 _Part III_

* * *

Claire shakes off Castiel's hand and steps forward. The seam of her flannel shirt is split at the shoulder, and her dark makeup is tear-smudged and running. "Randy…"

It's an unsteady accusation laced with a fair amount of disbelief, and Dean feels for the girl. He does. But they've done what they came here to do, and he'd like very much to skip past the teenage emo portion of this outing. "Get her out of here," he orders Cas. There're no monsters here, but humans are just as crazy and unpredictable – if not more so – and this entire thing could go sideways in the span of a blink. They weren't raised to kill men but they'll do what they need to, and both he and Sam have tense fingers on their respective triggers.

"Yeah," Sam seconds firmly, tightening his grip on his gun in a way that screams more of his reluctance to pull the trigger than it does his willingness to do so. There isn't much threat in the gesture, and he seems to want to get the hell out of here just as badly as Dean does. Likely more. "Go."

Cas complies wordlessly, tucks Claire away under his arm and steers her toward the exit. Dean _feels_ that they're gone from the house more than he sees them leave, and immediately turns to his brother, herding Sam likewise toward the door. "Go."

Sam ducks out quickly and Dean starts to back up, eyes widening when the goons move to follow.

"Hey, back up," he barks. "Back up!" The two lackeys are spaced apart just enough that he's having hard time keeping his eyes on both of them. Dean lifts his gun, jaw clenched to the point of pain.

It starts not at the site of the Mark on his arm but in his very core: a hot ache of long-caged discontent sensing a looming point of egress.

He swallows. "Don't be as dumb as you look." _God_ , he wants them to listen, doesn't want to risk unstopping the cork and unleashing that…thing.

They do, mercifully; both men halt their approach and concede the upper hand to Dean and his raised pistol. He bobs his head in satisfaction, takes another step back.

"Hey!"

Dean reflexively, however stupidly, turns toward the call, dropping his shoulder and his guard because despite the incessant push of the fire rising inside, he's struggling _so_ _damn_ _badly_ to keep that violence in check, to squash the bloodlust boiling in his veins. He doesn't want to come around swinging, or worse.

Pain like a sharp sunburst explodes in Dean's head before he realizes the guy's bringing something down on him, and he falls hard to the floorboards amidst the sounds of shattering glass and his own grunt. In a red haze of blurred vision and spiking agony, he loses control of his gun as it clatters away from his hand, and then – however momentarily – control of everything else.

The dam breaks and the heat floods through him, overtakes him: that initial, fierce burn when Cain clutched his arm, the power in holding the Blade for the first time, the incomparable _relief_ and satisfaction in killing Magnus with the weapon, the unbridled, unchecked fury in fully giving himself over to the demon within.

Then it's gone, and Dean's senses come back like the tight snap of a rubber band. He shakily pushes up from the floor, right arm feeling tight and hot; a searing sort of heat that's worming through the rest of him at a speed he's not sure he can slow on his own. He registers the achy pulse of the open wound in his head, the trickle of blood down his face and that warmth spreading through his veins, drying him out. A begging thirst he won't dare quench.

He _won't._

He blinks to clear his vision, raises a trembling hand and stares intently up at the men moving in on him. There are three of these stooges and he's still on the floor, but there's no way in hell he loses this fight. Not the kind of fight they're looking for.

Dean the man wants them to back the FUCK up, but Dean the bearer of the Mark of Cain wants them to try it. Wants to find out exactly how much fight each of them has in him before blood is not only spilled but run out. Their blood; not his. "You guys don't wanna do this."

He doesn't know if it's a threat or a plea, but Dean's never wanted anyone outside of his brother to listen to him so _badly_.

The guy standing over him rubs at his mouth and quietly chuckles in that cocky, stupid way Sam had laughed that time he took a swing at Dad. That one time. Then he rears his foot back and connects solidly with the side of Dean's head.

Dean loses himself in the motion of springing back with the speed and ferocity of a fired bullet, of kicking that son of a bitch's legs out from under him with a vicious, audible _snap._

He goes down with a yell of pain that barely registers on landscape the of Dean's awareness. It is, however, as good as a rung dinner bell for the other two. The toe of a pointy, polished shoe digs into Dean's ribs and flips him roughly onto his back.

He's lost his gun – and for the moment, his breath – but it'll be a cold day in Hell when Dean Winchester walks into a possible fight with only one weapon on his person. In this moment of disconnect, of weakness, his fingers twitch for the First Blade between them, two halves of one whole.

He has _a_ blade, and that'll have to do for now.

These guys are tough and pissed but sloppy, cleaned out Randy's fridge waiting for the girl. There are empty bottles everywhere, and booze on their breath. But they don't make it easy for him to get the knife in his hand.

Dean's reeling from a punch and pinwheeling backwards into the other room before he even realizes he's made it to his feet, and everything in the house is hazy and tinged with red, his arm pulsing with such pain it's likely to consume him. But only if he lets it. Only if he loses it.

And he _won't._

Douchebag number one is a bit gimpy but armed with a giant-ass ring on his right hand, with a solid gemstone at its center that _cracks_ against Dean's cheekbone when he brings his fist down.

He gets a couple of clean hits in, solid strikes that bruise flesh, that pop someone's nose and at least one of his fingers, and the entire time Dean's feeling like he's dangling from the end of a very short rope, and his head feels hot and fat, every one of his bones poised to crack in half.

A raging, consuming sort of pain that Dean knows will abate if he just gives _in_. Just gives himself over to the Mark.

 _No,_ he thinks fiercely, and staggers back with the heel of his hand pressed to the violent pound in his temple. A weight sharply impacts his chest and he hits the flat of the table on his back, a flare of pain bursting from his ribcage as something inside of himself gives at the same time as the table's legs.

Dean grunts and rolls as he drops to the floor, reflexively snaking his arm around to reach once more for the knife at his belt as shadowy figures close in. He finally manages to get the hilt of the blade in his hand, and as he's raising the weapon one of them grabs his wrist and gives it a horrible twist.

A nauseating _tear_ and tortured howl fill the room, and Dean thinks they might have both come from him, but the fresh flare of agony in his wrenched wrist yanks the rug out from under any semblance of control he'd been clinging to up until this point.

The curtain rises for the Mark of Cain, and things go pretty quickly after that.

* * *

 _To be concluded in Part IV._


	4. Part IV

**Showtime**

 _Part IV_

* * *

"Are you okay?"

"Yeah."

Sam takes vague note of the hushed exchange between Castiel and Claire as he drops behind the steering wheel, shooting an appraising glance over the bench at his passengers. Claire might've played at being a badass, but she looks every bit a scared young girl now, her arms wrapped tightly around the angel. Cas has stiffly, hesitantly returned the gesture, valiantly playing the part of the forever-lost father whose costume he's wearing.

Just as Sam's realizing that the opposite end of the seat is vacant and they're one short of a full car, a muffled, tortured shout and violent crash resound from the house beyond the Impala. And then, a quick succession of more obvious sounds of a fierce struggle taking place within. Where Dean is.

 _Dean._

Heart tripping, Sam's out of the car and hopping back onto the porch with his gun in hand before he really comprehends that he's moving, and doesn't notice that Claire and Cas have followed him in until the girl screams.

That's when Sam sees the blood. The bodies.

Cas pulls Claire close and tucks her face away against his chest, looking just as horrified by the scene as Sam himself feels.

There's a frightening moment of severe disconnect between his eyes and his brain, as he dumbly scans the interior of the house and is unable to accurately locate his brother among the spills of carnage. His jaw drops with a shout, a plea, a… _something_ on his lips when he finally, mercifully spots Dean. Not among the sprawled, carved bodies but looming over them, bloody blade still in hand. The reluctant victor slumped, winded on his knees.

"Dean?" Sam shakily tucks the gun away and rushes forward. "Dean, hey."

There's no response from his brother as he hits his own knees in front of Dean. Not towards Sam, anyway.

Dean's eyes skip right over him like he's not even there, go about roaming the landscape of the room and seemingly taking note of every drip and splash of blood, of each shredded, twisted body, and recoiling at the sight like he's being repeatedly struck. Like he's seeing it all for the first time, yet all the same, knows better.

Of course he did it. _Of course_ he did. The blade in his hand is circumstantial evidence; it's the goddamn Mark of Cain that screams of Dean's guilt, burning tangibly hot beneath layers of jacket and shirtsleeve, permeating the air around them and stifling each of Sam's breaths.

This is everything Sam has been anticipating and dreading and it's completely his fault, because he left Dean in the house. Against training and better judgement. Against an entire life spent watching one another's six, he left his brother alone and open to attack, when Dean was coiled as tight as he's ever been, poised to strike back. To _kill._

There's more than enough blood already on Sam's hands as he grabs Dean's grimy face and grips tightly, forcing his brother to meet his wide-eyed gaze. Without preamble or ceremony or opportunity to entertain denial, he demands, "tell me you had to do this."

"I did – " The thick, gravelly word gets lodged in Dean's throat, lost in an obvious struggle to say _anything_ , because it truly seems beyond the scope of his abilities to be articulate at the moment. "I didn't mean to."

 _No._

"No," Sam presses, grabbing desperately at his big brother, holding onto Dean with everything he's got and trying to keep him _here_. To not lose him to the Mark. "Tell me it was them or you." He hasn't made such a heavy, weighted demand of Dean in years. Hasn't felt so much like a needy _little brother_ in years.

Dean's rapidly roving eyes can't stay focused on Sam, and they widen even more as his gaze lands again on the spread of bodies around them. His mouth drops open, breaths coming hoarse and ragged, but he doesn't say anything to put his little brother's mind or heart at ease, which is an admission in itself.

In the silence, Sam finds his hands dropping away.

There's a muted, high-pitched keening from behind him, and Sam jerks his chin in the direction of the sound, surprised to see the room empty. "Cas," he calls, in a voice that's lacking emotion and just loud enough to reach the porch, "get her out of here."

The angel ducks his head into the space left by the ajar front door, eyebrows drawn together in concern. "But Dean – "

"I've got Dean." Slow and steady, so as not to spook his brother, who seems to have retreated into himself in the span of a breath, who seems to be both here and really, incredibly _not_. "Take her…I don't know. Figure it out."

"Sam – "

"Their car's outside." Without taking his eyes off Dean, Sam waves vaguely in the direction of one of the bloodied, mangled bodies. "Probably got the keys on 'em." He listens to the floorboards creaking cautiously underfoot as Castiel moves through the room to search pockets.

"Sam," Cas starts as he straightens, staring down at the blood-tinged jumble of metal in his hand. "I should really – "

"Just get out of here!" Sam finally all but shouts at the angel. He presses his lips together, sends a few deliberately spaced exhales through his nostrils. "Go," he says, quieter and calmer, or at least acting pretty well like it. _Go._ Like Dean had said. "We'll be okay here."

Once Cas is gone, he turns back to his brother. Specifically, to the vacant gaze in Dean's eyes, and the knife still clenched in his white hand. "We're okay here, right? Dean?" He wants to freak out, he really does. But it's clear that Dean's not completely _here_ , and Sam needs to keep it together for both of them.

It hits him then, that this – whatever _this_ is – it might not _be_ the Mark, but simply what's been left in its wake. A wounded man who's spilled and sacrificed and served his purpose well enough. There's blood on Dean's face that's clearly his own, and each inhale he makes is choppy enough, familiar enough, to warn Sam of further injuries beneath the surface.

It was a fast fight, that's for sure. The time lapsed between that first shout to Sam stepping into the aftermath can't have been more than a couple of minutes. More than enough time for an amped-up Dean to both give and receive a fair amount of damage. The room has been _torn apart_ , and Dean is slowly slumping over where he still kneels.

Sam reaches out once more, steadying his brother with a firm hand at the junction of neck and shoulder. "What's going on here, Dean? You hurt?"

Dean's chin comes up a bit at the sound of his voice, but his eyes screw up in confusion. "Sam?"

He tries to smile, but can't say for sure that he succeeds in this venture. "Dean, hey. Yeah. You need to talk to me, man." Sam's fingers slip in a track of warm wetness at the back of Dean's neck, and when he checks his fingertips they're bloody, and that answers one question. _Dammit._

He tips Dean forward too easily, finds a second wound buried in the short hair at the back of his brother's head. Sam could probably match it well enough to one of the broken bits of furniture in the room, but the source of the injury isn't his main concern. It's what happens _now._

Sam pulls back, studies his brother's slippery gaze. If that first blow didn't concuss him, the second one clearly did. Dean's eyes are glassy and unfocused, his pupils uneven and blown to hell. But this look is familiar, and more than concussion, or pain. It's retreat. It's _shock._

His injuries are myriad but seem mostly superficial – likely rib bruising or fractures, given the state of the room and Dean's deliberately shallow breathing, but that's an easy enough fix and aside from the head wounds, there's no obvious blood loss. Nothing to explain shock of a _physical_ nature.

"Okay," Sam says quietly to himself, putting that knowledge into the bank for later. There are, somehow, more pressing matters than his brother coming to pieces before his eyes, because he still has to get the knife out of Dean's hand. Without knowing what exactly it was that sent the man hurtling over the edge in the first place, what brought him to do little more than butcher four men in the space of a few minutes, it's extremely possible that Sam's never been more afraid of his big brother in his life.

Or _for_ him. For what this means.

Because whether or not these guys were dicks, and whether or not they deserved it, they were MEN. This wasn't hunting; it was _murder_.

This wasn't just everything Sam was fearing, but everything the Mark of Cain has been _screaming_ for, and pushing Dean to deliver.

They provoked him, though; that's for _damn_ sure. Sam winces, surveying the full catalog of damage not caused _by_ his brother, but done _to_ his brother. The jagged cut in his hairline isn't the worst he's ever had, but coupled with the second wound in back, it's bad enough. Most of the blood on Dean's face is his own, stemming from that gash, and there's very possibly glass embedded in his scalp. From the beer bottle left shattered near the entryway, Sam realizes, feeling sick. The left half of Dean's face is blooming with fresh bruising, deep patterns that Sam likewise recognizes as the heel of a boot.

He'd been on the floor, Sam realizes angrily, remorse and sympathy for the dead ebbing away. Possibly concussed, outmanned and at a disadvantage, but if he has anything at all left in the tank, Dean Winchester doesn't stay down long.

And with the Mark of Cain at his side, he hadn't actually been either outmanned _or_ at any kind of disadvantage.

Like he's coming up for air, Dean sucks in a big gulp of air that blows his eyes wide. He gasps and winces, almost like he's feeling all of that pain in his body for the first time. He spots Sam in his face, frowns. "Wha – Sammy?"

It'll be a brief window of clarity and clear-thinking, if Sam's extensive experience with dealing with his wounded brother is any indication. He has to act quickly. "Yeah. Hey. Let me just – can I have this?" Sam raises his eyebrows at the knife still clenched in Dean's right hand.

Dean follows Sam's gaze down to the knife. His fingers twitch around the hilt of the blade but he nods slowly.

Sam keeps his eyes on his brother's face as he reaches out to relieve him of the blood-streaked weapon, and as soon as he touches the hilt Dean grunts and pulls away, releasing the knife altogether to drop to the floorboards with a clatter. He makes a wordless protest as he moves to cradle the hand, some wounded, guttural sound that twists Sam up in knots.

Just when he felt like he was almost in control of the situation, like he almost had the puzzle assembled, it topples like a Jenga tower with that _hurt_ noise from his brother. Sam wonders idly if this is anything similar to the way Dean's been feeling. "Okay, okay. Hold on a sec."

Dean makes a face and tries to pull his hand away, but Sam quickly grabs him by the elbow, stabilizing his arm and keeping Dean from concealing whatever injury he's looking to hide. With his brother biting on his lower lip and staring off at some nondescript point across the room, Sam gently tugs his jacket sleeve up.

Dean's wrist is grotesque and purpled, the joint nearly completely concealed by swelling. Probably sprained, possibly broken. They'd certainly aimed to make it hard for him, to kill them. Yet with each discovered injury, no matter what had happened in this house, Sam can't help but feel fractionally more justified on his brother's behalf.

Any one of his injuries could have been the one that toggled that switch Dean has had such a desperate grip on. Any singular, vicious burst of pain could have engaged his already sensitive fight or flight instinct, and coupled with the influence of the Mark…this isn't really Dean's _fault_. But it is his problem. And by association, Sam's.

There are four bodies here, but Dean's blood seems to be mostly confined to his own skin and clothes. It's a morbid and possibly unfair thought, but Sam can't help but feel that even with the Mark of Cain steering the car, his brother wouldn't have been stupid or careless enough to touch printable surfaces in this house.

Sam lets his brother's hand rest gently against his thigh and sits back on his heels to assess their situation. This is more than ibuprofen and Ace bandages in the bunker. This is a now-obvious concussion, and likely multiple breaks, and some form of shock. This is easily an ER run, but Sam isn't sure he can risk taking Dean anywhere so bright and open and aggressively _public_ right now. Not when he's twitchy and traumatized and just _murdered_ four people.

A siren sounds off in the distance, and Sam's time for deliberation is up. It doesn't matter if it's headed for them or not – the threat is out there. The REALITY of this unquestionably precarious situation is out there. He needs to trust his instincts and focus on his brother. Needs to get Dean home. Now.

"Can you stand?"

Dean sniffs, nods. Winces. Doesn't speak.

Sam returns the motion. "Okay."

Stand, yes. Walk? That's a different story entirely, and Sam does most of the work that takes place between the spot where Dean…stopped, and the open front door.

The thugs' car is gone from the driveway, Cas halfway to who-the-hell-knows with a shaken Claire in tow. He knows he'll have to contact the angel, steer them in the direction of the bunker, keep everyone close. There doesn't seem to be an end in sight for Sam's responsibility.

Dean is a heavy and hesitant weight pressed against his side as they make their way to the Impala, like he isn't really trying to move forward with the steps Sam is taking.

Sam really, fiercely hopes that isn't something that's going to stick.

* * *

Sam settles down at one of the tables in the bunker's main room, feeling wired and unbelievably tense despite the fact he's been up and running for nearly forty-eight hours now. He needs to rest, to get some _sleep_ , but he wants to plant himself directly in the path of any possible escape route. He can't figure Dean will really be independently mobile for at least another day, but if the stubborn jackass does give it a go, he won't be able to make it to the garage or main door without Sam spotting him.

A part of Sam hates himself for even worrying that his brother might try to make a break for it, for whatever reason, but another part of him really, truly _expects_ it.

The door scrapes open and Sam raises his tired eyes, watches Cas enter. "How's Claire?"

"She slept the entire way." Cas stops at the foot of the staircase, keeping an awkward, unnecessary distance.

Sometimes Sam really just wants the guy to sit down and stop putting them all on edge. He rolls his eyes, covers the motion by rubbing at them with both hands. "That's good."

"Dean?"

Sam sighs, dropping his hand to smack hollowly against the tabletop. "Less sleep. And, uh, less good. Where's Claire now?"

"I've gotten her a room at a motel in town."

Sam jerks his chin toward one of the empty chairs at the table with him. He waits for Cas to take the hint and sit before nodding. "You think she'll stay there?"

"I don't believe Claire's going anywhere for a while," Castiel says, almost sounding like he means to assume the guilt for this entire mess. "She's…shaken."

"Yeah." Sam looks away, taps his fingertips against the polished wood. "I think it's safe to say we all are."

Cas's gaze shifts down the narrow hallway branching away from the main room. "And now? How is he?"

"Not good. Not at all." Sam sighs again, straightens in his chair and squares up to the angel. "And I think it's past time we all stop pretending any differently, before…just before. We're going to do everything we can to figure out how to get the Mark off of Dean."

"And if we can't?"

"Then we're gonna help him find a way to live with it. No one else gets hurt because of this damn thing. Including Dean." Sam raises his eyebrows. _Show's over._ "Let's get to work."

* * *

 _The End_

 _Author Note: So this became a little more than I had anticipated, especially since I hadn't anticipated writing any of it, and my muse was just stuck in a corner one day being quiet and stubborn so my muse's muse hit it with the inspiration stick. Seriously, y'all should get a muse for your muse. They're pretty much the best thing ever._


End file.
